Burning of carbon electrodes



S. E. SIEURIN.

LUHNING 0F CARBON ELECTRODES.

APPLICATION FILED JULY 31.1920.

1,390,32.?Y L Pandsept. 13,1921.

` of which the following is a specification.

UNITED STATES PATENT oFFlcE.

SVEN EMIL SIEURIN, OF HGANS, SWEDEN. Y

BURNINGQF cannon nnncrnonns.

To allfwhomit may comer-n:

Be it known that' I, SVEN EMIL SIEURIN, a Subject of the King of Sweden, residing at Hgans, Sweden, have'invented new and useful Improvements in the Burning of Carbon Electrodes, (for which I have filed an application in Sweden on Sept. 16, 1918,)

This invention relates to 'an improved process and apparatus for producing carbon electrodes in an electric furnace, the principal object of the invention being to provide a process and apparatus by means of which the gasification of the volatile components of l so that it becomes itself a conductor, and asv the electrode may take place from the `exterior toward the interior of the electrode, thereby permitting the deposit on the electrode of the graphite resulting from the gases, and by means of which apparatus the resulting electrode is without cavities such as are ordinarily produced by the insertion of a metal core in the material from which the electrode is formed.

In the drawings accompanying and formin part of thisrspecification,

lgure 1 is a fragmentarysectional view of an electric furnace adapted for carrying out the present invention; and Fig. 2 is a similar view illustrating a metallic member for initiating the burning of the carbon electrodes. The same characters of reference designate the same parts in the different figures of the drawings.

In the manufacture of carbon electrodes which are usually produced. by the calcination in an electric furnace ofa-plastic mass of coke or other carbonaceous material and a binding substance, for instance, tar, it has heretofore been the practice to place one or more metal cores, usually of iron, within the carbonaoeous mass from which the electrode is to be formed, said cores being surrounded by an insulating, iireproof material. The purpose of these cores is to act as conductors for the electric -currentuntil the carbonaceous mass has been suicientlyburned soon as the temperature in the furnace becomes suiciently, high the metal cores are melted. This procedure has the disadvantage that the electrodes produced will be partially intermixed with the metal of the` fused ormelted core unsuitable for the for instance.

and thereby rendered production of' aluminum, Moreover, by reason'of the is inclosed within modified form of Specication of Letters Patent. Patente-d Sept- 13, 1921.. Application led July 31,

1920. serial No. 400,514. l

` mit the depositing of the graphite resulting from the gases upon the surface of the electrod'e, which deposit of graphite is very-'advantageous for` thereason that it increases the conductivity of the electrode.-

In order to overcome the disadvantages above referred to, the present'invention provides a process and apparatus by means of which the plastic a jacket of insulating material and the metallic heat initiating means is disposed outside of said mass and separated therefrom by said insulating material.

Referring to the the furnace, within which are` placed the blocks 2 of plastic material to be burned, each block being-incased in a jacket 3 of insulating material. As illustrated'in Fig. 1, the metallic means for initiating theheating of the block is in the form of rods 4 em bedded in the walls of the insulating jacket, while in Fig. 2 the initial heating member is illustrated as formed of a metal tube 5 inclosing the insulating jacket. It will, of

thus be seen that by this procedure each of the blocks forms an elect 'ode without cavities formed by the metal members a/nd owing to the fact that the heating begins at the drawings, l designates the metal members may outside, the gasification ofthe volatile components of the blocks also proceeds from the outside toward the center, 'thus permitting the ,deposit of the graphite from the gases on the surface of the electrodes.

mass which is to be burned u Having thus described my invention, what 'A I claim is:

1. The process of producing a carbon elec?- trode which consists in placing a `mass of electrode forming material `in an electric furnace, surrounding the same with meta1- lic heat initiating means insulated therefrom, passing a current through said means to heat said mass to a predetermined degree, removing said heat-initiating means and continuing the heating through the instrumentality of the mass itself.

r2. The process of producing a carbon electrode Which consists in placing a mass of electrode forming material in a jacket of insulating lmaterial in an electric furnace, passing a current through metallic heat initiating means associated with said jacket and heating said mass until it becomes conductive, removing said heating means,` and continuing the heating through the mass itself.

3. An apparatus for burning carbon electrodes, comprising an electric furnace, metallic heat initiating means in said furnace for each electrode to be burned, and an insulating jacket associated with said heat initiating means and adapted to receive the electrode forming material.

4. An apparatus for burning carbon elec trodes, comprising an electric furnace, a metal jacket in said furnace for each electrode to be burned, and an insulating jacket Within said metal jacket and adapted to receive the electrode forming material.

ln testimony whereof I have Signed my `name to this specification.

SVEN EMIL SIEURIN. 

